Reconciles the session-surface work (surfaceOp/sourceEventSeqs provenance as
the sole derivation path) with master's worktree-subagent series (fork-seed
boundary + out-of-process subagent backends).
Semantic reconciliations beyond the textual auto-merge:
- SQLite SCHEMA_VERSION: both sides bumped 2->3. Merged to a single v3 carrying
BOTH column families — master's seed_length on `sessions` and surface's
source_event_seqs/surface_op on `events`. writeRow + both INSERT sites bind
the full set; the schema doc lists all three added columns as the v2->v3 gap.
- agent-loop runStep request: master's `sessionId: session.id` and surface's
per-append surfaceOp/sourceEventSeqs coexist (different regions).
- Fork seed + surface: a fork seeds the child from the parent's LIVE events,
which now carry surfaceOp, so the child's surface rebuilds correctly. Verified
end-to-end — the subagent-fork replay recalls the inherited "SAFFRON" codeword
through the seeded prefix.
- Subagent snapshot fixtures (recorded pre-surface) re-enriched via KEYLESS
deterministic replay: only surfaceOp/sourceEventSeqs added onto existing
recorded lines (matched by seq), no recorded value changed. Not re-recorded
against the live API.
Gates: typecheck, test (1112), test:snapshot (14), doc-sync, lint, build,
hygiene all green.
The snapshot tier was built single-session: dsh-llm-replay served calls from
one global positional cursor, and the harness harvested one session log. A
subagent runs as a second agent with its own session, so a parent→child
scenario could neither replay deterministically nor harvest the child's log.
This resolves the TODO(subagent-snapshots) deferral from the subagent RFC.
- Stamp the calling session id onto the model request: GenerateOptions.sessionId
(typed Branded<'SessionId'> to avoid the dsh-llm↔dsh-session cycle), set by the
agent loop from agent.session.id. Adapters ignore it; an llm/stream listener
routes by it.
- Key replay per session: dsh-llm-replay loads the parent log plus one per child
(childFiles / $DSH_SNAPSHOT_CHILD_FILES), derives a script per recorded session,
and binds each live (freshly-random) session to a recorded script by first-call
order — parent first (earliest createdAt, first to stream). Keys by WHO calls,
so it survives a future concurrent/backgrounded subagent; a global cursor would
not. An unrecorded extra session fails loud.
- Harvest every log: the harness collects all .jsonl across cwd buckets, ordered
primary-first (top-level, then children by createdAt), and RunResult exposes the
plural sessionLogs. The spec writes each back on record (session.jsonl +
session.<n>.jsonl) and diffs each against its fixture on replay.
- Wire the subagent seam + spawn + fork + tool into the acp-agent example (both
cordis configs) and add two nested scenarios recorded against the real API:
subagent-spawn (parent + 1 child) and subagent-multi (parent + 2 children, 3
sessions). Both replay keyless in the default gate.
A new RFC documents the design (docs/rfc/implemented/testing/). Single-session
replay is unchanged (a call with no sessionId is one anonymous primary session).
TODO follow-up: a dedicated branded-ids package could own the SessionId brand and
dissolve the cross-package cycle note; out of scope for this testing PR.
